In recent years, there has been an increased focus on reducing emissions of greenhouse gases generated by burning fossil fuels. One solution for reducing greenhouse gas emissions is developing renewable sources of energy. Particularly, energy derived from the wind has proven to be an environmentally safe and reliable source of energy, which can reduce dependence on fossil fuels.
Energy in wind can be captured by a wind turbine, which is a rotating machine that converts the kinetic energy of the wind into mechanical energy, and the mechanical energy subsequently into electrical power. A plurality of wind turbines generators may be arranged together in a wind park, wind farm or wind power plant to generate sufficient energy to support an electrical grid. A wind power plant may be located onshore or offshore, and it often covers large geographical areas. Each wind turbine generator typically includes or is connected to a wind turbine controller, and the wind power plant typically includes a central controller, often referred to as a power plant controller, central controller or master controller, operatively coupled to the wind turbine controllers of the individual wind turbine generators. The power plant controller is arranged to receive information from the wind turbine controllers, e.g. in relation to the power output and/or measurement values from the wind turbine generators, and the power plant controller is arranged to transmit information to the wind turbine generators, e.g. in order to obtain a requested output from the wind turbine generators.
These factors usually render it necessary to provide a variety of networked interconnections and communication technologies for monitoring and controlling the wind power electric generating facilities.
In a wind power plant with a plurality of wind turbine generators, the focus has moved away from the separate wind turbine generator connection points to the central wind power plant connection point, often referred to as the “point of common coupling”, and the control of individual wind turbines is supplemented by an overall control carried out by a wind power plant controller or master controller, arranged to control the components of the wind power plant by transmitting setpoints on e.g. active and reactive power to be provided at the point of common coupling. In very large wind power plants, more than one point of common coupling may exist, and more than one power plant controller may exist. One limiting factor when performing central control of a wind power plant with several wind turbine generators is the time it takes to gather and condition information from the individual wind turbine generators, transmitting the information to the central controller or power plant controller and distributing control data, e.g. new active or reactive power set points from the power plant controller to the wind turbine controllers.
The term “components of the wind power plant” is meant to denote the energy producing or energy generating components of the wind power plant, viz. the wind turbine generators and optionally compensation equipment capable of generating electrical output.
It is an important task for the power plant controller to provide optimum set points on active and reactive power to be generated by each of the wind turbine generators and compensation equipment, if it is comprised in the wind power plant.